Network services provided by Carrier Ethernet service providers, such as Ethernet virtual private line services and Ethernet virtual private LAN services, facilitates network connections between multiple geographically remote customer locations via Ethernet Virtual Connections (EVCs). When the customers utilize VLAN tags, the tags may be included in the data traffic that is transmitted across the EVCs. If the VLAN tags are accessible to a third party, the third party may be able to adjust the VLAN tag. However, inappropriate adjustment of VLAN tags may leak information from one VLAN to another VLAN. Such adjustment may also result in incorrect computations for certain Layer 2 control protocols, such as Generic Attribute Registration Protocol Multicast Registration Protocol (GMRP).